1. Field of the Invention
The present invention relates generally to masonry arch forms, and more particularly to a removable flexible masonry arch form assembly which may be removed after construction is complete.
2. Description of the Related Art
An arch is generally known as a structure for spanning an opening between two end points located at substantially equivalent elevations. Masonry arches are utilized in both residential and commercial facades and provide an aesthetically pleasing aspect to various types of architecture. Masonry arches may be formed to span various openings and are used in home and building construction to span radiused windows, doorways, or other arched structures providing an aesthetically pleasing appearance. The arch is architecturally significant because, in theory at least, it provides a structure which eliminates tensile stresses in spanning an open space. Masonry arches function by transferring vertical loads laterally to adjacent voussoirs and, thus, to the end points or abutments. All the forces are resolved into compressive stresses, which is useful because several of the available building materials such as brick, stone, and pre-cast concrete can strongly resist compression but are relatively weak when tension, shear or torsional stress is applied to them. By using the arch configuration, significant spans can be achieved. Further, the arch is a very useful structure as it is completely self-supporting since all of the compressive forces hold it together in a state of equilibrium.
Arches generally have end points or abutments which stabilize the arch and a keystone at a central, generally uppermost, location of the arch. Downward force in the arch causes thrust in the arch from the keystone to the abutments placing the arch in uniform compression. For purpose of this description, the arches are generally formed of masonry elements which may be understood to include brick, stone, precast concrete, terra cotta or other such material having good compressive strength and further comprising a mortar bonding material.
During installation of masonry arches, contractors generally utilize wooden sheets of plywood cut in an arch shape having a radius approximating the radius of the adjacent arched structure, for example window. This is time consuming because a separate wooden form must be cut for each window or arched structure as well as those structures with different radii. This type of construction wastes time and material since wood for forms must be purchased which would otherwise not be necessary for the project. Usually, the forms are discarded after construction and therefore must be made again for a subsequent construction project.
Other types of costly arch forming tools are utilized some of which are permanently installed in the building construction. Most regions, however, do not require such permanent construction and therefore it is preferred, for aesthetic reasons, to remove the arch form following the construction of the masonry arch. With many types of forming tools, this is not possible since the tool is permanently fastened to the substructure of the building before the masonry arch is formed over top of the structure.
Given the foregoing, it will be appreciated that a more affordable arch forming device is needed which may be removed following construction of the arch.